Gas barrier laminate and packaged article, and method for producing gas barrier laminate

a technology of gas barrier and packaging material, which is applied in the direction of packaging foodstuffs, packaged goods, other domestic articles, etc., can solve the problems of aluminum oxide vapor, low disposability, and content decay, and achieve high oxygen barrier properties, excellent strength and transparency, and high oxygen barrier properties.

Active Publication Date: 2007-05-17
KURARAY CO LTD
View PDF2 Cites 34 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0008] With such a situation in mind, one of the objects of the present invention is to provide a gas barrier layered product that exhibits a high oxygen barrier property regardless of humidity, exhibits a high oxygen barrier property even after being subjected to retort processing, and is excellent in strength and transparency. Furthermore, another object of the present invention is to provide a method that allows such a gas barrier layered product to be manufactured industrially advantageously.
[0009] The present inventors made keen studies assiduously to achieve the above-mentioned objects. As a result, they found out the following. That is, when a layered product including, as a gas barrier layer, a layer formed of a composition that contains: a hydrolyzed and condensed product of metal alkoxide; and a polymer containing at least one functional group selected from a carboxyl group and a carboxylic anhydride group is immersed in a solution containing a metal ion with a valence of two or more and thereby the above-mentioned functional group contained in the polymer is neutralized, the characteristics of the layer formed of the above-mentioned composition improve dramatically. Then further studies were made. As a result, the present invention was completed.
[0013] The present invention makes it possible to obtain a gas barrier layered product that exhibits a high oxygen barrier property regardless of humidity, exhibits a high oxygen barrier property even after being subjected to retort processing, and is excellent in strength and transparency. It is possible for the gas barrier layered product of the present invention to have an oxygen transmission rate of 1.0 cm3 / m2·day·atm or lower in an atmosphere of 20° C. and 85% RH. This gas barrier layered product can be produced industrially easily by the production method of the present invention. The gas barrier layered product is used effectively for packaging materials for foods, medicine, medical equipment, machine parts, and garments, for example. Above all, it is used particularly effectively for food packaging in which a gas barrier property is required to be obtained under a high humidity condition.

Problems solved by technology

Particularly, with respect to food packages, the presence of oxygen allows microorganisms to proliferate and thereby the contents decays, which is a problem.
However, metal layers such as the aluminum vapor deposition layer and aluminum foil have disadvantages in that the packaged contents cannot be seen or disposability is low, for example.
Furthermore, metal compound layers such as the silicon oxide vapor deposition layer and the aluminum oxide vapor deposition layer have disadvantages in that the gas barrier property thereof is degraded considerably when the packaging material is deformed, dropped, or subjected to an impact during transportation, for example.
However, in a state where it has absorbed moisture due to, for instance, water vapor, the hydrogen bonds are loosened and thereby the gas barrier property thereof tends to deteriorate.
Accordingly, it is difficult to allow a vinyl-alcohol-based polymer such as polyvinyl alcohol to exhibit a high level of gas barrier property under a high humidity condition.
The above-mentioned conventional techniques, however, cannot satisfy such demands well.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Gas barrier laminate and packaged article, and method for producing gas barrier laminate

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0152] Polyacrylic acid (PAA) with a number average molecular weight of 150,000 was dissolved in distilled water. Thereafter, ammonia water was added thereto and thereby 1.5 mol % of the carboxyl groups of the polyacrylic acid were neutralized. Thus, a polyacrylic acid aqueous solution was obtained, in which the solid content concentration was 10 wt %.

[0153] Next, 68.4 parts by weight of tetramethoxysilane (TMOS) was dissolved in 82.0 parts by weight of methanol. Subsequently, 13.6 parts by weight of gamma-glycidoxypropyltrimethoxysilane was dissolved therein. Thereafter, 5.13 parts by weight of distilled water and 12.7 parts by weight of 0.1N (0.1 normal) hydrochloric acid were added thereto. Thus, a sol was prepared. This was allowed to undergo hydrolysis and condensation reactions at 10° C. for one hour while being stirred. The sol thus obtained was diluted with 185 parts by weight of distilled water, which then was added promptly to 634 parts by weight of the above-mentioned 10...

example 2

[0160] First, the layered product (1) described in Example 1 was produced. On the other hand, magnesium acetate was dissolved in distilled water in such a manner as to have a concentration of 10 wt %. Thus, an aqueous solution was prepared, and it was kept warm at 80° C. The layered product (1) was immersed in this aqueous solution (80° C.; MI-2) for approximately 20 seconds. Thereafter, this layered product was removed therefrom. Then the surfaces of the layered product were washed with distilled water whose temperature had been adjusted to 80° C. After that, it was dried at 80° C. for five minutes. Thus, a layered product (B-2) of the present invention was obtained. With respect to the layered product (B-2), the neutralization degree of the carboxyl groups of the polyacrylic acid contained in the gas barrier layer was determined by the aforementioned method. As a result, it was proved that 64 mol % of the carboxyl groups had been neutralized by magnesium ions. In addition, with re...

example 3

[0162] First, the layered product (1) described in Example 1 was produced. On the other hand, zinc acetate was dissolved in distilled water in such a manner as to have a concentration of 10 wt %. Thus, an aqueous solution was prepared, and it was kept warm at 80° C. The layered product (1) was immersed in this aqueous solution (80° C.; MI-3) for approximately 20 seconds. Thereafter, this layered product was removed therefrom. Then the surfaces of the layered product were washed with distilled water whose temperature had been adjusted to 80° C. After that, it was dried at 80° C. for five minutes. Thus, a layered product (B-3) of the present invention was obtained. With respect to the layered product (B-3), the neutralization degree of the carboxyl groups of the polyacrylic acid contained in the gas barrier layer was determined by the aforementioned method. As a result, it was proved that 60 mol % of the carboxyl groups had been neutralized by zinc ions. In addition, with respect to t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
RHaaaaaaaaaa
hazeaaaaaaaaaa
temperatureaaaaaaaaaa
Login to view more

Abstract

A gas barrier layered product and a method for producing the same are provided. The gas barrier layered product exhibits a high oxygen barrier property regardless of humidity, exhibits a high oxygen barrier property even after being subjected to retort processing, and is excellent in strength and transparency. In order to provide the gas barrier layered product, the gas barrier layered product includes a base material and a layer stacked on at least one surface of the base material. The layer is formed of a composition that includes: a hydrolyzed and condensed product of at least one compound (L) containing a metal atom to which at least one characteristic group selected from a halogen atom and an alkoxy group has been bonded; and a neutralized product of a polymer containing at least one functional group selected from a carboxyl group and a carboxylic anhydride group. At least a part of the —COO— group contained in the at least one functional group has been neutralized with metal ions having a valence of two or more.

Description

TECHNICAL FIELD [0001] The present invention relates to a gas barrier layered product and a packaging medium as well as a method for producing a gas barrier layered product. BACKGROUND ART [0002] Materials for packaging foods and various articles often are required to have a gas barrier property, particularly, an oxygen barrier property. This is intended to preclude effects such as oxidation degradation of packaged contents that is caused due to oxygen, for example. Particularly, with respect to food packages, the presence of oxygen allows microorganisms to proliferate and thereby the contents decays, which is a problem. Hence, in conventional packaging materials, gas barrier layers that prevent oxygen from permeating therethrough are provided, so that the permeation of oxygen is prevented, for example. [0003] Such a gas barrier layer can be, for example, a vapor deposition layer of metallic foil, metal, or a metal compound. Generally, aluminum foil, an aluminum vapor deposition lay...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(United States)
IPC IPC(8): B32B27/00B32B29/00B05D1/40B05D3/02B32B27/28B32B27/30C08J7/043C08J7/048C08J7/052
CPCB32B27/08Y10T428/1341B32B27/28B32B27/30B32B27/308B32B2255/10B32B2255/26B32B2264/105B32B2307/412B32B2307/7244B32B2439/70B32B2439/80B32B2553/00C08J7/047C08J7/06C08J2367/00C08J2433/00Y10T428/1352Y10T428/24802Y10T428/1334B32B27/18Y10T428/31504Y10T428/31993Y10T428/31663C08J7/048C08J7/052C08J7/043B32B27/20C08J7/0427
Inventor OSHITA, TATSUYAUEHARA, GOKINAKAHARA, ATSUHIROKAZETO, OSAMUSHIBATA, MANABUMIYAMOTO, TAKEHIRO
Owner KURARAY CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap